waxing prolix

June 24, 2009

What color is Twitter?

En route to another thing I'm working on, I built a little color scraper that scans the Twitter public timeline for words describing colors. Any word that is a CSS3 web color name (which some of you graybeards may remember as similar to, but not exactly, the X11 colors), is detected and the corresponding R, G, B triple is saved. For example, consider the following tweet:

Finally found the WoW Mt. Dew Game few...the red one is good, but the blue one tastes like ass...

Because I only grabbed the first color in a tweet, the above results in red (255,0,0). Getting a few hundred of these took a day (6/24/2009), as the Twitter API limits how often you can query it. Consequently, most color tweets were missed. However I got enough to make the picture above, where every pixel corresponds to a tweet mentioning that color.

June 6, 2009

Song of the Orbs

So we've been refreshing the sound modules on SWARM, and have been experimenting with multitrack audio. The idea is that you can, with one command, get all the orbs to play back different mp3 files at the same time, and they will stay roughly synchronized. Erik found some great multitrack Flaming Lips and a highlight of running the orbs was tooling around on the mothership, very late one night, to the sounds of the Orbs singing.

This sounded so good that I was inspired to make my own music for the Orbs. Originally this was a 64 minute audioscape I procedurally composed as an aid to insomnia (as much as I love Eno's Thursday Afternoon, there's only so many times you can listen to something, plus it's a little sparse to mask noise very well). It's not really a song, as nothing really happens: it's essentially a "Steve Reich ninth chord" (my specialist terminology) with some high-Q filter sweeps that pick out harmonics above. I re-mastered it as six separate stereo tracks, one for each robot; since it's one chord they will naturally harmonize. Seeing as how you likely don't have spare robots rolling around, here it is as one long track to soothe your insomnia (it's not particularly exciting): song_of_the_orbs.mp3 (77 MB)

May 25, 2009

Son Shiva

Here's another one you can see at Maker Faire. This one I made a while ago from six disk drive head actuators that are triggered in different sequences. Pressing a button on the game controller triggers one of eight sequences.

May 23, 2009

Rotation Simulator

Something else just up as a preview for Maker Faire 2009: the Rotation Simulator.

This is a kinetic artwork that digitally simulates rotation and inertia. Turning the knob sequentially triggers eight solenoids arranged in a circle, giving the impression of rotation. The speed and direction is proportional to the knob rotation, and exponential decay simulates rotational friction mimicking an actual rotating object. However the only thing actually rotating is the knob! The LEDs are used as flyback diodes and flash when the magnetic field in the solenoid is switched off.

Here are the guts for those interested in the geeky stuff. As usual, follow the link for an annotated descriptions.

May 20, 2009

Ghostmatrix

Well, this was supposed to be a weekend hack. Only it took a few months. In any case, it's kind of working now! What is it? It's a light printer that uses an array of UV LEDs mechanically scanned across phosphorescent paper, leaving a matrix of glowing dots that slowly fade. Hence "ghostmatrix." I scavenged the linear motor from SRL discard pile, and used an Adafruit Mini POV3 with custom software as the light engine. Here's a video of the beast in action:

Ultimately I want to hook this up so it will print tweets. Not there yet, but it will be @ghostmatrix on Twitter. Need to figure out how to get DMs or @replies into an RSS feed, or just buckle down and use the API.

Here's a closeup of the business end. Follow the link to see the labeled parts.

And for you geeks, here's the Frankensteined driver board. I thought it would be easier to reuse the existing board (only need access to 6 signals) but tracing wires on the autorouted multiple-layer board was the very definition of a PITA.

I should give credit where it's due; I used the "Atari-Small" 8x4 font from Tom's X11 Fonts and the spiffing Python bdflib font manipulation library.

UPDATE: some more information about parts and sources: the phosphorescent paper is Grafix "Funky glow In the Dark" and a web search should get you the source. The lightpipes were (if I recall correctly) purchased from mouser.com. If they are still available I could not find a part number, but a similar (if shorter and more expensive) product is this: http://www.mouser.com/Search/Refine.aspx?Keyword=696-C011701S-150C

Ripple Matrix

This is a recent interactive artwork I'm just getting around to documenting. I showed it at the "TV of Tomorrow" conference in April.

This work is a 8 x 15 array of full-color LEDs, driven by an embedded Linux board. Each LED is addressable, and optical sensors make the work interactive if you touch it. I'm running a digital simulation of the 2-dimensional wave equation. Think of water in the bathtub: it's quiescent when not disturbed. However triggering an optical sensor does the digital equivalent of throwing a rock in a pool: it disturbs the initial conditions, and sends ripples propagating away.

May 15, 2009

My bitchin' coffee table

This is a coffee table I built from a salvaged Textronix 7704A oscilloscope mainframe I pulled from a dumpster. A sheet of glass on top and a wooden frame complete the table. (I added the frame because I kept bumping my shin on the invisible glass!)

Though I had hopes of resurrecting the scope (originally a 5-figure piece of quality test equipment), it had sat in the rain for a little too long. The PSU in particular had about 14 different output voltages, some of them high, and was completely fried. So I removed some shielding to expose the beautiful insides and made it into a bitchin' coffee table.

April 12, 2008

Chassis at the San Jose Museum of Art

So Chassis had his first paying gig at the SJMA last night. After some opening-night jitters (I can't believe we hooked up the keg tap backwards!) things went completely smoothly, and the beer ran out at precisely 9:00 PM when the reception ended.

I'm continually surprised and amazed just how willing people are to treat a a vaguely-humanoid piece of junk like a person.

April 9, 2008

Finally done

After more than a year, this custom 1440-LED installation I did for a private residence is finally up. What you see here is less than 1/5 of the whole thing (I couldn't get a shot of the big living room panel because of construction equipment in the way). It came out pretty great. Pictures show snaps of two different video programs ("reflections" and "sparkle"). (I'll get some video up as soon as I can figure out how to rotate it in a way that doesn't break the video sites.)